Experimental batchesofpolymerthickenedgreases,aswellastheirbaseandbleed-oilswere
tribologically characterizedthrough film thicknessmeasurementsoverawiderangeofentrainment
speeds onaball-on-disctestrigusingopticalinterferometry.Theresultsareinagreementwithprevious
observationsofseveralauthors.Underfully flooded conditionsandlowspeeditwasobservedthat
thickener lumpsenterthecontactproducingahigh film thicknessplateau.Thetransitionspeedatwhich
the film thicknessincreaseswithdecreasingspeedisdependentonthethickenercontentandoperating
temperature.Atmoderatetohighspeeds,allthetestedgreasesshowa film thicknessmuchhigherthan
the baseandbleed-oils,eventhoughthebleed-oil's film thicknessisclosertothegrease's.